Hide "Restart job" for failed jobs if the plug-in doesn't support restarting

[Nicklas Nordborg]

For most jobs this is not a problem, but some plug-ins require parameters that are part of the current gui context. Those parameters doesn't survive a failure. The best example is the "Table exporter" plug-in which throws a NullPointerException:

java.lang.NullPointerException
at net.sf.basedb.clients.web.plugins.SimpleExport.performExport(SimpleExport.java:328)
at net.sf.basedb.core.plugin.AbstractExporterPlugin.run(AbstractExporterPlugin.java:144)
at net.sf.basedb.core.PluginExecutionRequest.invoke(PluginExecutionRequest.java:110)
at net.sf.basedb.core.InternalJobQueue$JobRunner.run(InternalJobQueue.java:510)
at java.lang.Thread.run(Thread.java:619)

A possible solution would be to define a tagging PluginType interface (eg. NonRestartable). The gui can check if this interface is implemented and then hide the Restart job and Reconfigure job buttons (in the View job dialog).

[Martin Svensson]

(In [5404]) Fixes #1508 Hide "Restart job" for failed jobs if the plug-in doesn't support restarting